Seawater column antenna
When I first joined NARL, the Newington Amateur Radio League (the local repeater club, not the national association), the first meeting's guest speaker was touting a do-it-yourself antenna made from a column of saltwater. New to the hobby and not having an engineering background, this sounded amazing to me. Later some old timers at the club took me into their confidence and assured me this was an April Fool's gag and the antenna was little more than a "dummy load." I thought it was a pretty good gag.
Years later, I saw a video by SPAWAR System Center Pacific, purportedly a defense contractor with a pending patent for an antenna made of a stream of seawater pumped through a magnetic inductor. Darned if they didn't demonstrate that it worked, both as a jet of water in open space, and confined in a plastic tube. They claimed it worked on HF, VHF and UHF by adjusting the length of the water column. You can find it if you Google "seawater antenna." I still don't know if this is real or an elaborate gag. But it sure falls in the category of "strange antennas."
--AB1GL, George Lillenstein, Manchester, CT
ab1gl@arrl.net